Ok, I want to put a Deathbox INSIDE of a Housewrecker, then put the Housewrecker INSIDE an Imperial, Then put the Imperial in the back of my truck. What would that sound like? Should I install a camper shell on my truck for more gain?

Bob :-/

By the way, I took pics of the face of my Niles, then disassembled the cabinets and photo'd the inside. Have to develop the film to post. ::)

[quote author=Bob in St. Louis link=board=Housewrecker;num=1145573673;start=240#251 date=06/13/06 at 12:14:03]Ok, I want to put a Deathbox INSIDE of a Housewrecker, then put the Housewrecker INSIDE an Imperial, Then put the Imperial in the back of my truck. What would that sound like? Should I install a camper shell on my truck for more gain? [quote]

outrageous man...

lets see, theoretically the two tunings would average the output from the db, yeilding two 'smaller than a normal HWK' spikes, which would in turn be amplified by the imperials horn...

so the system would have a fairly restricted output (low efficiency), likely resembling the comb effect of voight pipes, except distributed across the imperials response curve instead of a flat line. Likely this would sound like @$$-mike + a long stairway, but with excellent power handling...

I think you were kidding though... but the camper shell would help the gain a bit, by lowering it, that would be your only hope of achieving decent loadiung of the horn

I still think you are kidding, but a useless post is never truly appreciated until it is justified by an equally useless response.

[quote author=jj420 link=1145573673/240#252 date=1150223593] I still think you are kidding, but a useless post is never truly appreciated until it is justified by an equally useless response.JJ [/quote]

Yea, I was joking. I was amazed at the amount of threads dedicated to fitting a home sub into a vehicle. Had to add my own flavor. Didn't want to trash someone else's thread, sooooo,... naturally had to trash my own. :)

Thanks for the quick response though. Shame our last two post were useless (you were correct JJ)

Ok. B.S. aside. I've got pics and numbers. (Pics of surround drivers to be posted on webshots later today. Hopefully)

John, I played with some toys over the weekend. I have db numbers from 1 meter away from the bass of the sub at a hz range from 90hz, down to 10hz. ( yea, 10hz ) in 5hz increments. The first column is db's, second and third columns are hz's with the top cap on, then removed, respectively. cap cap on off

With cap on (middle column)--Imagine a graph, (from right to left) you could see a small climb, to a peak of 119 between 65-70hz, with a gradual slope back down below about 20 hz where the slope falls sharply. (need to find my graph paper, just to see the pretty picture). Interesting thing happens there in the teens with the cap off. The damn thing falls off in the same place, but is doing pretty well in the 'bottom of the well' so to speak.Back on post #193, I said "18hz@130db may not be obtainable on a budget, but I 'might' be happy with 18hz @105db." Well, the proofs "in the puddin'" as they say. John, thanks to you, I've got 20hz@105db. May play around with increments in 1hz from 15 to 20hz to see if we're there, but that's pretty damn close if nothing else.

BTW, 2 year old daughter can maintain 101db's when she's pissed, with an occasional peak to 108db. HZ is unknown, but painful.

Sound quality is perfect for movies (my goal) the torture tracks/chapters faired very well. The amp knob is now actually at about 1 o'clock (60%) during these tests. If memory serves, I believe I posted earlier that the knob was around 40%, and drivers were bottoming before the mods were performed.Sound quality for music is ok, (granted the knob is at around 10 o'clock for music) but havn't sat down to actually LISTEN to some tunes without the family around. But what listening I've been able to do, does sound favorable.

Yea 60, I think you might be right. I believe you told me about them before and somehow, during the search, I got hold of a porn site that was tinypic...something. I though you were B.S.ing me at the time.

Glad you sound happier. If the sub wasn't in the corner for the measurements, you should give that a try. That should give you some more boost. For music you need to stuff the port for better sound, because an EBS type alignment will sound too loose with music.

BTW some simple mods should help those Niles. I can't tell, are the cones of the woofer paper or plastic? They need some deadening and bracing on that thin plastic cab, along with some stuffing in there. Just for grins do a sound comparison with one open plus a piece of cardboard to extend the baffle and the other speaker stock.

Do a similar measurements on one of the Niles. Not max, just at a moderate set volume to see what extension they have on both ends and a general idea of response across the spectrum. Any big peaks or nulls?

The Flintstones are the first pair of OBs I ever made in finished form and that was 2 years ago, when I was a noob. What you want is my next similar set, although you might consider something similar and cheap in the meantime. Use the guts of your Niles + 2 pairs of cheap 6x9's or 5x8's per side, as a simple test venture into OB's.

Yes, sub was 1' from the right wall, and 6" from rear wall, with port facing back of seating.

Paper/Plastic; You know,...I'm not really sure. I'll have to look at them better. They're fairly shiny, like plastic, but couldn't promise that. I'll check.They have a nice thick/dense white batting in there. Actually some pretty impressive stuffing. Hate the plastic though.

Sounds like a weekend type project with the testing. Probably a better idea to check the same speaker (sealed then apart) instead of two different one's I'd imagine?

Liken' that OB thing. (read the WHOLE DarkStar thread, all 87 pages to date. Lots of stuff 'over my head')I suppose a guy could just grab some mdf and cut 3 pieces, poke some holes, and see how it sounds. And some bracing of course.

[quote author=Bob in St. Louis link=1145573673/255#261 date=1150841382]Sounds like a weekend type project with the testing. Probably a better idea to check the same speaker (sealed then apart) instead of two different one's I'd imagine? [/quote]

No, it's a 5min project. No, not just one and stuff the woofer port and turn the XO cutoff up much higher to help fill in the bass. Tape a piece of cardboard to each side of the opened up speaker to add some baffle to it. Then play some music and pan left and right to hear the difference between OB and boxed, keeping in mind that the bass mayl be severely lacking on the OB. With both playing though, the other one will fill in most of the missing bass, but you'll hear much more open and natural sound on the open speaker side. It's not subtle and you'll wonder why they ever started closing up speakers (bass more cheaply and higher power handling are the reasons. You want instant switching and direct comparison, because out audio memory is very short and only direct comparisons are worth much.

Quote:

Liken' that OB thing. (read the WHOLE DarkStar thread, all 87 pages to date. Lots of stuff 'over my head')I suppose a guy could just grab some mdf and cut 3 pieces, poke some holes, and see how it sounds. And some bracing of course. Bob

Cardboard and duct tape. If you want to spend a few $, get a couple of pieces of the posterboard with the foam core that architects use for models. Then with a serrated knife and tape you can try a few test speakers in minutes. Don't worry about bracing on test cabs. That's for a slight refinement at the end. You just need them to stand up.

Does your center channel have dual woofers? Once you go OB, you won't want the center anyway, so the drivers may be useful. Open it up too for pics.

Good advise John, I mentioned the weekend thing since I'd rather spend some 'quality' time listening to all of the various sources. The surrounds are wall mounted. Would you recommend I remove them, maybe set them on a stool further away from the wall for the "OB test"? Or should I just experiment?

The center is MTM. I've peeked in the rear port once, found nice supply of stuffing. But will photo some 'exploritory surgery'. I've heard about people not using centers for HT, I understand the imaging and soundstage a guy can create with proper drivers and placement, BUT what about discrete channels? What do you do with dedicated center material? Realizing an OB needs to be vertical with one end on the floor for bass, what about an OB center channel placed horizontal on legs? Center doesn't carry much bass anyway?

Would be cool if I could "bastardize" my speakers and make them all "baffleable". hmmm, rear surrounds too? ???

For seeing what OB is about, connect them in front in place of your mains and with the center channel turned off. Use whatever is convenient and place them some distance from the front and side walls for the test listening. Include music and some movie dialogue. I love OB's for music and they're even better for HT, because dialogue is much more clear and natural.

Regarding the center channel info. When you set your receiver to no center channel, then what usually goes to the center is sent to the mains.

[quote author=John in CR link=1145573673/255#267 date=1150922364]Mode would do the trick too, just 2 ch stereo. [/quote]

I think it's there....on the remote, however (since electronics ALWAYS know whats best for us ::) ) the receiver is in some kind of "mode" that will not let me select any of the functions like 2,3, 5, 7, channel surround, in addition to all of the various Dolby doohickeys. ::) It's locked on 7.1 surround (although the front/mains behind the screen have been unplugged for weeks) ....hmmm, may have to kick it. ???

OB may be my final frontier, I've tried just about every box style that I know of so far. I've got lots of high Q drivers but none that will go low enough to get down to 60 hz. Unless I could be convinced otherwise, I've got 8 eight inch drivers with Qts higher than .6 and fs of 57. Either OB or Frugal Horns, I don't have to decide for a few weeks yet.

Bob, this is what I would really like to see you try. Use the full HWK size box (all three chambers, full volume of the enclosure) with one driver only. Stuff the snot out of it with fibreglass. It would have to be retuned a bit higher but I don't think it would be too much higher. Then take your other driver and put it another HWK size box and put that in the other corner.

Same amount of power, same drivers but a whole lot louder. What's a couple more sheets of wood? I dare you.

p.s. They've also got (buried in the site, somewhere) a nice section where people post the "cool" scenes of a movie, ie.. super low LFE, exceptional surround track, good examples of surround, ect.ect...Kind of like the SVS site has a list of movies with super low LFE's.

Yes, +6db. If you have them in the front corners, you should also get some mutual coupling in the lower frequencies, which offset the added distance. Same tuning would require a shorter port due to the increase volume, so less port noise, but response would fall off a bit faster below tuning. Try first by just taking the top driver off. Then try it with your current port and just one driver in the top cap, which will tune you about 2hz lower. That should get you pretty close to 100db at the listening position, maybe more, at those lowest frequencies with the second box. The wave expansion from the front should sound better and blend easier, plus you should get some small gain due to placement at the end of your L shaped area instead of projecting from the corner into both sections of the L.

Nothing about the Xbox remote hack at RemoteCentral. It's only $9 + a USB connector and a little solder, so I'll be the forum guinea pig.

Looks like you have a big advantage being in the US. I paid $60 for 2 sheets of mdf and I thought that was pretty good. I paid $150 for my 15" Quatro (lists $15 cheaper than your Series II's) and I thought that was reasonable too.

It appears Canadians are paying roughly 2x the cost for the same materials. With this in mind, I think you owe it to yourself to make 3 more and get 12 db more output. So there.

No Bob, I'm no gamer, although I did play Resident Evil 2 for the PS1 until I got Tofu (no memory card help). The remote is just to control my PC (movies and music) instead of using my cordless keyboard as a remote control. It's just a simple cheap conversion.

Regarding your sub, you'd don't need another amp. Your current one is powering both, so it's the same thing, just 2 different boxes. Same power needed, etc.

[quote author=John in CR link=1145573673/270#276 date=1150994884]Regarding your sub, you'd don't need another amp. Your current one is powering both, so it's the same thing, just 2 different boxes. Same power needed, etc. [/quote]

Yea, I knew that for the dual sub arrangment my existing amp would work, it's when bassboy got radical on me and wanted a "Housewrecker array" that I would need more than one amp.

Sorry bassboy, I think I'll have to pass on 4 Housewreckers. :)Cool idea though. Say,... how many HWK'ers do you think 60 could stick in his minivan?

I'm just making one prototype to start, but if it works out well you can bet there will be at least one more in the other corner as time and money permit.

Depending on how serious you are about really low bass, it might be worth considering tl's. My Quatro models about 6 db louder at the same tuning in a tl vs. ported enclosure. The Series II doesn't model nearly as well in tl (down about 5 db compared to my driver), that's why I didn't buy one of those.

By the way, my box is under 16 cubic feet, outside dimensions, and takes up just over 2 square feet of floor space, how big is yours?

Full report in about T minus two weeks or so, lots of graphs and comparisons between different boxes and my Quatro 15. There's even a comparison between Quatro and Series II in a tl.

Well, I started my journey down the OB road this weekend despite the fact my receiver 'shot craps'. I felt like I was installing new tires on a totaled car. ::) Building speakers for a receiver that's broke.

Made some nice progress. I didn't have cardboard large enough, But I did have some leftover counter top (formica veneered particle board.)

Since I'm using "real material" as opposed to a temporary setup, I figured I'd do it right with symmetry, neatness, ect..ect..I got the 2 front baffles made, routered resseses for the drivers. Drivers are complements from 2 donor Niles OS-10 surrounds that were originally part of my system.

The wind has been let out of sails with no audio in my house, so I'm like a little kid who's favorite toy has been taken away.Not much enthusiasm.

Bob, got any regular 2 channel amps lying around? Maybe steal one from the shop or the kids?

It might be time for some 2.1 channel OB for a completely different experience. If you're going to get into OB, you might as well get completely immersed with only OB speakers (and sub of course). Any other box types playing the same frequency range are going to swamp the OB's and you won't hear why they are special.

Please don't go hacking your speakers up. We have no idea what those drivers are and they may not be suitable for OB. I didn't even want you to take them off of the existing baffle, just tape some small additions on to what was already there. You could have used some wood scraps or whatever. Then leave everything connected, original box behind the baffle, and give it a listen, a 5 or 10 miinute process to get an idea of what OB sounds like.

I think it's time for me to stop throwing out ideas and let you explore away. Feel free to ask questions any time. The reason I jumped in to begin with was that I hated to see you scrap a perfectly good cab, when I knew you could make some minor changes and achieve something closer to what you were looking for. If my new sub works out, I'll run the numbers with your drivers and see if something similar makes any sense for you.

I'll admit that I know very little about OB but I do know that high Q drivers work best. High Q = small magnet and lightweight material = drivers that can be very cheap. I would assume old factory car speakers and old cheap home drivers would work great. That equals free of charge. So now that you have a frame I would go ahead and use it with a wide assortment of different drivers to see what's possible. Small surround speaker drivers are probably not very suitable to OB but you should be able to get your hands on some good ones.

Other than the excellent resources here, there is a lot of info on other forums. A good place to start would be diyaudio.com.

I haven't been interested enough to study any of it yet but I would think that you could make something that sounds and looks very good for very little and maybe even no money. It might be hard to go as low as your sub crossover point for free though.

John, No speakers were harmed during the making of the baffle.The Niles screws were turned to the left, No damage done. Empty plastic enclosures complete with stuffing and screws are safely tucked away from the sawdust. If it all goes to hell, They can be reassembled. No harm done.

Please DON'T EVER STOP throwing ideas my way. Never, Never, Never.

When I build something, I don't take the time to make written plans. Because I'd probably change something anyway which would make the plans null and void. That goes for outdoor decks, indoor speakers, or entire finished basements. No plans. Ideas are generated and stored in the noggin. So when I set out to try OB, I did a quick inventory of my building materials and found that the Formica was some pretty cool lookin' stuff (the counter top is leftover from the bar in my pics.) Thought it would be cool if OB's matched the bar. Yea, I got carried away, took your idea to an extreme.My ideas sometimes get extravagant, but an audio noob with radical ideas can be a dangerous thing. John, I like your ideas, keep 'em comin'! ;D I'd rather build your ideas instead of mine. Granted, 'play time' in the workshop is a good learning experience for me, BUT, I'd rather build something with a more proven track record than what my brain can come up with.

By the way John, the drivers cones are plastic.The tweet's domes appear to be a synthetic fabric type material, VERY soft material, the dome deflects with very little pressure from a finger tip. They've also got one heckuva large magnet for a tweeter (IMHO).

Early Saturday morning I stopped by the local pawn shop to check for orphaned drivers. All they had were large car subs, and guitar amps. A couple local flea markets (huge one's) may be a good place to explore. Havn't been in years.Unfortunately being a noob, I wouldn't have a clue what I'm looking at a far as what is acceptable for what type of enclosure (unless of course is says Visaton B200 ;D). And I'm sure the drivers sitting on a table at a flea market arn't going to have T/S numbers.

Yes, the formica to match the bar would have been nice to use, but now you've used it on test baffles.

In general, you're looking for smaller magnets. That is usually an indicator of higher Qts. Ideas for cheap- The 8" Pioneer full ranger from parts express for $25. Check out car audio installation shops for the factory drivers they remove from the rear deck of cars. Most of the whizzer coned 6.5" in the back dash are used in a free air alignment (IB), so their parameters are perfectly suited for OB use, and they typically sound surprisingly good especially with a tweeter added to the top end.

I'm currently planning an OB bass augmenter manifold with B200's as the main driver. They'll end up being quite compact floor standers with the woofer section 8-9" wide and 25" tall, which will contain 8 6"x9"s in each speaker. They will be the equivalent of a pair of 15" woofer, but in a compact depth and drastically lower price. Something very similar to my Flintstone cabs, but slightly taller.

Exactly, you just can't see the drivers through the front pathways because I put a piece of expanded metal over the opening from the back and those driver frames and entire chamber are painted black. The work behind that is invisible but I was very worried about vibration noise from the grill and went to significant lengths to prevent it. The new one will move a lot more air and will require a larger grill approach. I'll also have to equally air mass load the back side too.

Those look nice, John.Are they going on stands or do you plan to angle them upward slightly.The idea is similar to what I was trying figure out. I want to incorporate a "W" baffle into the main, with the 2 - 15s running push-pull. I like the use of smaller drivers in multiples, but I am a little spoiled with the low Fs (22Hz) the JBLs have.

I was using a MTM arrangement (2 - 15s + B200) for about a month and that really sounds great, but I tried to flip one of the drivers around and the difference is amazing. They remain that way, for now, but I'm getting tired of looking at (and bumping into) a 20 lb magnet structure.

Those are about 2 years old and were one of my initial forays into OB. I didn't plan for enough surface area on the augmenters and they sound really good, but only up to moderate levels. The reason I want to try the 6x9's is that I can pack them into a more compact depth. That way any depth in excess of 10" is 2 for one value and makes it a hybrid U-baffle. That way I can keep it really compact, plus less pathway depth means I can cross as a higher frequency making main driver options more flexible. My goal is to see how compact I can go with a high performance without cheating and boxing up the bass. Whether I ever go to market with it is irrelevant to me. I'm just having fun trying to do what no one else has, create a domestic size OB with real bass that can be driven by a single amp.